There are many circumstances in which it is important for performers creating sound to have a reliable, timely and reasonably precise indication of the intensity of the sound being created. Such performers include, without limitations, solo singers, singers who are part of a group of singers, solo instrumental musicians, instrumental musicians who are part of a group of musicians, individuals giving public addresses, and theatrical performers. Reliable, timely and reasonably precise indication of the intensity of the sound being created can be useful during practice and during public performance.
Electric and electronic systems which display indications of sound intensity are well know in the art. Most have displays that are too small to allow ready viewing more than a short distance from the display. That makes them unsuitable for use by many sorts of performers (e.g., for direct use by members of a singing group).
There are systems which display indications of sound intensity in manners which allow that indication to be seen by more distant viewers. For example, Yacker Tracker (Creative Toys, Fort Collins, Colo.) and Talk Light (Talk Light, Inc., Garland, Tex.) are systems styled in the likeness of traffic lights. The systems are designed for use in places such as classrooms and school cafeterias. Two sound intensity thresholds can be set by the user. If the detected sound intensity is below both thresholds, the green light is illuminated. If the detected sound intensity is between the two thresholds, the yellow light is illuminated. If the detected sound intensity exceeds both thresholds, the red light is illuminated. Although other uses are possible, the primary use is to encourage children to keep the noise level within acceptable bounds. Such a system is disclosed by Fran Rebello in U.S. patent application Ser. No. 09/876,024. Systems of this type would have limited usefulness as sound intensity feedback for performers, because of the limited number of intensity thresholds.